A comparative study of safety perceptions, concepts and practices in two technologically complex industries: the primary Mozal aluminum smelter, located in Beluluane, near Maputo (Mozambique), and the Petrogal oil refinery in Sines (Portugal). The main methodological instrument of the project is the direct observation of long duration, complemented by interviews, documentary analysis and short questionnaires, intended to quantify (a posteriori) phenomena detected during direct observation. Based on material and theoretical reflections resulting from previous research, the immediate aim of the project is to understand the learning processes of industrial technology and technological rationality, and how labor hazards and other threats are perceived and conceptualized according to different possible logics, such as probabilistic “risk”, unpredictable “danger” and / or local systems of domestication of uncertainty. Secondly, the project seeks to understand the consequences of such notions and practices (and the interactions they maintain) for limiting or enhancing the hazards inherent in the work of these plants.